Influence range specifying method, influence range specifying apparatus, and storage medium

ABSTRACT

A non-transitory computer-readable storage medium storing a program that causes a computer to execute a process, the process includes determining an information transmission path between two devices with a correlation in use status of resources based on system configuration information and use resource information; generating, for each of a plurality of software, an influence propagation model in which a direction from a first device to a second device is set as an influence propagation direction, when a co-occurrence probability that the second device outputs a message within a certain time after the first device outputs a message through execution of the software is equal to or greater than a threshold, based on a message log; acquiring failure information indicating a failed device; specifying an influenced device reached by tracing the information transmission path from the failed device in an influence propagation direction; and outputting information indicating the influenced device.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of InternationalApplication PCT/JP2017/046678, filed on Dec. 26, 2017 and designated theU.S., the entire contents of which are incorporated herein by reference.The International Application PCT/JP2017/046678 is based upon and claimsthe benefit of priority of the prior Japanese Patent Application No.2017-006312, filed on Jan. 18, 2017, the entire contents of which areincorporated herein by reference.

FIELD

The embodiments discussed herein are related to an influence rangespecifying method, an influence range specifying apparatus, and astorage medium.

BACKGROUND

Many of devices coupled to a computer network system cooperate withother devices, and the state of a device may depend on the state ofanother device. Therefore, when a failure occurs in a device of thesystem, a device dependent on the device is also influenced. Theinfluenced device may operate slower than usual or may not be able tooperate. For example, when a device A is a server, and a device B is aclient of the server, the operation state of the device B depends on theoperation state of the device A. When the device A stops due to afailure, the device B may not be able to perform normal operation. Forexample, a large number of devices depend on each other in a large-scalesystem. Therefore, a failure in a device affects the device and a devicedirectly coupled to the device, and besides, a large number of otherdevices.

Under the circumstances, when a failure occurs, it is important topromptly notify a user or a system administrator of the influenceddevices and the influence range.

Whether there is an influence relationship between devices in the systemmay be determined based on, for example, whether there is a correlationbetween the devices regarding the use status of resources. For example,when the timing of an increase in the load of the central processingunit (CPU) coincides in two apparatuses, there is a correlation betweenthe two apparatuses regarding the use status of the CPU. It is likelythat one of the two apparatuses depends on the other.

Alternatively, whether the devices are in the influence relationship mayalso be determined based on a co-occurrence relationship of logs. Forexample, when two apparatuses output messages, such as error logs, atsubstantially the same timing, the apparatuses are in the co-occurrencerelationship of logs. It is likely that one of the two apparatuses inthe co-occurrence relationship of logs depends on the other.

An example of a technique related to investigation of the influencerelationship between apparatuses includes a failure analyzing apparatusthat specifies a failure-causing functional element that is a functionalelement predicted to be causing a system failure. There is also anoperation managing apparatus that enables to present a failed part and acause of the failed part in an understandable way. Furthermore, there isalso a dependency information collecting system that automaticallycollects and stores dependency information between devices or servicesto reduce the load of managing the dependency and that is alsoconfigured to specify a device influenced upon failure or the like andto figure out the importance of the failure. There is also a controlmethod of a high-availability computer system that executes a failureprevention and recovery process. In the control method, the effect andthe influence of the failure prevention and recovery process are takeninto account to determine whether to execute the process or to optimizethe execution order of the process. In addition, there is also aninformation processing system that accurately specifies a tenant and acommunication path influenced by a failure when a failure occurs.

Examples of disclosed related art include International PublicationPamphlet No. WO2010/016239, International Publication Pamphlet No.WO2010/032701, Japanese Laid-open Patent Publication No. 2006-178834,Japanese Laid-open Patent Publication No. 2008-009842, and JapaneseLaid-open Patent Publication No. 2015-211374.

However, the difference in dependency between devices regarding eachpiece of software is not taken into account in the related art, and theinfluence range of a failure of software may not be properly specified.For example, even when a failure of a piece of software propagates fromthe device A to the device B, a failure of another piece of software maypropagate from the device B to the device A. The influence range of afailure in a piece of software may not be accurately specified bydetermining the influence range of the failure without considering thedifference in propagation direction of the influence of failureregarding each piece of software. In view of the foregoing, it isdesirable to be able to accurately specify the influence range of afailure of software.

SUMMARY

According to an aspect of the embodiments, a non-transitorycomputer-readable storage medium storing a program that causes acomputer to execute a process, the process includes determining acommunication path between two devices with a correlation in use statusof resources as an information transmission path based on systemconfiguration information indicating a coupling relationship between aplurality of devices included in a network and based on use resourceinformation indicating temporal variation in the use status of theresources of each of the plurality of devices; generating, for each of aplurality of software, an influence propagation model in which adirection from a first device on the information transmission path to asecond device adjacent to the first device is set as an influencepropagation direction of a failure of the software in the informationtransmission path, when a co-occurrence probability indicating aprobability that the second device outputs a message through executionof the software within a certain time after the first device outputs amessage through execution of the software is equal to or greater than athreshold, based on a message log storing messages output by theplurality of devices through execution of the plurality of software,respectively; acquiring failure information indicating a failed devicein which a failure occurs in one of software among the plurality ofsoftware; specifying, as an influenced device influenced by the failurein the failed device, a device reached by tracing the informationtransmission path from the failed device in the influence propagationdirection indicated in the influence propagation model of the one ofsoftware; and outputting information indicating the influenced device.

The object and advantages of the invention will be realized and attainedby means of the elements and combinations particularly pointed out inthe claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the invention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 depicts a configuration example of a system according to a firstembodiment;

FIG. 2 depicts a system configuration example of a second embodiment;

FIG. 3 depicts a configuration example of hardware of a managementserver used in the second embodiment;

FIG. 4 is a block diagram illustrating failure influence range detectingfunctions of a management server;

FIG. 5 depicts an example of information stored in an operation stateinformation storage unit;

FIG. 6 depicts an example of information stored in an influencepropagation model storage unit;

FIG. 7 is a flow chart illustrating an example of a procedure of aninfluence propagation model creating process;

FIG. 8 depicts a detection method of an information transmission path;

FIG. 9 depicts an example in which information transmission pathsoverlap;

FIG. 10 is a flow chart illustrating an example of a procedure of aninformation transmission path detecting process;

FIG. 11 is a flow chart illustrating an example of a procedure of a pathextracting process;

FIG. 12 is a flow chart illustrating an example of a procedure of a pathdeciding process;

FIG. 13 depicts an example of determining an influence propagationdirection;

FIG. 14 is a flow chart illustrating an example of a procedure of aninfluence propagation direction determining process;

FIG. 15 is a flow chart illustrating an example of a procedure of adirection providing process;

FIG. 16 depicts an example of supplementing an influence propagationdirection;

FIG. 17 depicts examples of supplement patterns of an influencepropagation direction;

FIGS. 18A and 18B are flow charts illustrating an example of a procedureof an influence propagation direction supplementing process;

FIG. 19 is a flow chart illustrating an example of a procedure of adirection supplementing process;

FIGS. 20A and 20B are flow charts illustrating an example of a procedureof a weighting process;

FIG. 21 depicts an example of searching an influence range upon failure;

FIG. 22 depicts an example of an influence propagation model when aplurality of pieces of software operate together;

FIG. 23 is a flow chart illustrating an example of a procedure of afailure handling supporting process;

FIGS. 24A and 24B are flow charts illustrating an example of a procedureof an influence range searching process;

FIGS. 25A and 25B are flow charts illustrating an example of a procedureof a searching process;

FIG. 26 depicts an example of displaying an influence range of failure;and

FIG. 27 depicts an example of displaying an influence propagation rangewhen a plurality of pieces of software operate together.

DESCRIPTION OF EMBODIMENTS

Embodiments will now be described with reference to the drawings. Aplurality of embodiments may be combined within a compatible range tocarry out each embodiment. The term of “influence” used in the followingexplanation is sometimes called “failure impact”.

First Embodiment

A first embodiment will be described.

FIG. 1 depicts a configuration example of a system according to thefirst embodiment. An influence range specifying apparatus 10 is coupledto a network N including a plurality of devices M1 to M4. The influencerange specifying apparatus 10 is an apparatus that specifies aninfluence range of a failure when a failure occurs in software executedby any one of the devices. The influence range specifying apparatus 10is, for example, a computer that executes an influence range specifyingprogram describing a processing procedure for specifying the influencerange of the failure.

The influence range specifying apparatus 10 includes a storage unit 11and a processing unit 12. The storage unit 11 is, for example, a memoryor a storage apparatus included in the influence range specifyingapparatus 10. The processing unit 12 is, for example, a processorincluded in the influence range specifying apparatus 10.

The storage unit 11 stores system configuration information 11 a, useresource information 11 b-1, 11 b-2, . . . corresponding to the devices,and message logs 11 c-1, 11 c-2, . . . corresponding to pieces ofsoftware to be managed. The system configuration information 11 a isinformation indicating a coupling relationship between the plurality ofdevices M1 to M4 included in the network N. The use resource information11 b-1, 11 b-2, . . . is information indicating temporal variation inthe use status of resources in the plurality of devices M1 to M4,respectively. The message logs 11 c-1, 11 c-2, . . . are informationstoring messages output by the plurality of devices M1 to M4 throughexecution of corresponding software. Although the message logs 11 c-1,11 c-2, . . . correspond to the pieces of software in the example ofFIG. 1, one message log may be held for the entire system as long as anidentifier of the software causing the output of the message is set ineach message.

The processing unit 12 executes the following process based on theinformation stored in the storage unit 11.

The processing unit 12 first determines that a communication pathbetween two devices with correlation in the use status of resources isan information transmission path based on the system configurationinformation 11 a and the use resource information 11 b-1, 11 b-2, . . .. For example, the processing unit 12 calculates a correlationcoefficient of time-series variation in the use status of resources ofeach of the two devices and determines that there is a correlationbetween the two devices regarding the use status of resources when thecorrelation coefficient is equal to or greater than a given value. Twodevices may be exchanging information to cooperate with each other whenthere is a correlation between the two devices regarding the use statusof resources. Therefore, the processing unit 12 determines that thecommunication path between the two correlated devices is an informationtransmission path used to transmit information.

The processing unit 12 then generates an influence propagation model 13based on the message logs 11 c-1, 11 c-2, . . . . For example, theprocessing unit 12 calculates a co-occurrence probability of output ofmessage between a first device and a second device for each of aplurality of pieces of software. The co-occurrence probability is aprobability that a second device adjacent to a first device on theinformation transmission path outputs a message through execution ofsoftware within a certain time after the first device outputs a messagethrough execution of software.

When the co-occurrence probability is equal to or greater than athreshold, the processing unit 12 sets a direction from the first deviceto the second device as an influence propagation direction of a failureof corresponding software in the information transmission path togenerate an influence propagation model 13. For example, the processingunit 12 sets a propagation direction in the direction from the firstdevice to the second device for a first adjacent coupling relationshipthat is a coupling relationship on the influence propagation model 13between the first device and the second device in a relationship inwhich the co-occurrence probability is equal to or greater than thethreshold (co-occurrence relationship). The processing unit 12 furthertraces the information transmission path in the direction opposite thefirst device from the second device and sets a propagation direction inthe traced direction for a second adjacent coupling relationship that isa coupling relationship on the influence propagation model 13 betweenthe devices on the traced path. In the example of FIG. 1, a device C isthe first device, and a device B is the second device. In this case, theprocessing unit 12 sets the direction from the device C to the device Bas the propagation direction of influence for the influence propagationmodel 13. The processing unit 12 further traces the informationtransmission path in the direction opposite the device C, which is thefirst device, from the device B, which is the second device, and detectsan adjacent coupling relationship between the device A and the device Bon the traced path. The processing unit 12 then supplements thedirection from the device B to the device A as a propagation directionof influence along the traced direction of the information transmissionpath.

Subsequently, the processing unit 12 acquires failure information 14indicating a failed device in which one of a plurality of pieces ofsoftware is failed. The processing unit 12 that has acquired the failureinformation 14 specifies devices, which may be reached by tracing theinformation transmission path from the failed device in the influencepropagation direction indicated in the influence propagation mode of onepiece of software, as influenced devices influenced by the failure inthe failed device. The processing unit 12 then outputs influenced deviceinformation 15 indicating the influenced devices.

In this way, the influence propagation model 13 is created for eachpiece of software, and the influence propagation model 13 correspondingto the software with a failure is used to specify the devices influencedby the failure to accurately specify the influence range of the failure.The failure may be efficiently handled by accurately specifying theinfluence range of the failure.

Moreover, the correlation between the devices regarding the status ofresource usage and the co-occurrence relationship between the outputmessages are combined to reduce the chance of specifying a device notinfluenced by the failure as a device influenced by the failure bymistake. For example, the propagation direction of the influence offailure is not taken into account in the method of using the correlationbetween the devices regarding the use status of resources. Therefore,although a downstream device in the propagation direction influenced bythe failure is supposed to be specified as the influence range, anupstream device not influenced by the failure is also detected. Thus,the processing unit 12 uses the co-occurrence relationship between thelogs to define the propagation direction of the influence and traces thedevices in the propagation direction of the influence from the devicewith the failure to specify only the devices as devices influenced bythe failure. In this way, a device coupled in the direction opposite thepropagation direction of the influence from the device with the failureis not output as a device influenced by the failure even when the deviceis in the information transmission path. This improves the accuracy ofspecifying the influence range of the failure.

In generating the influence propagation model 13, the processing unit 12may set a weight according to the number of information transmissionpaths passing through an adjacent coupling relationship, for each of aplurality of adjacent coupling relationships indicating couplingrelationships between adjacent devices on the influence propagationmodel 13. In the case where the weight is set, the processing unit 12outputs information indicating the weight of the adjacent couplingrelationship when the processing unit 12 outputs the influenced deviceinformation 15. In this way, when a failure of software is to behandled, the devices may be handled in descending order of importance toefficiently handle the failure.

When the processing unit 12 acquires failure information of a failurerelated to two or more pieces of software, the processing unit 12 mayspecify the influenced devices based on the influence propagation model13 of each of the two or more pieces of software. In this way, a failureinvolving a plurality of pieces of software cooperating with each othermay be efficiently handled.

Second Embodiment

Next, a second embodiment will be described.

FIG. 2 depicts a system configuration example of the second embodiment.A network 20 includes devices to be monitored, such as servers 31 a, 31b, . . . , terminal apparatuses 32 a, 32 b, . . . , storage apparatuses33 a, 33 b, . . . , and network devices 34 a, 34 b, . . . . A monitoringserver 30 monitors these devices. The monitoring server 30 is a computerthat monitors devices on the network 20. The monitoring server 30periodically acquires information indicating the use status of the CPUand the memory from, for example, each device. The monitoring server 30acquires, from each device, a log of messages output by softwareoperated in each device. The monitoring server 30 further detects afault of each device. For example, the monitoring server 30 periodicallytransmits a signal for confirming the existence to each device anddetermines that there is a fault in the device that does not respond tothe signal for more than a given period.

The management server 100 acquires information from the monitoringserver 30 and detects the influence range of a fault when there is afault in any one of the devices.

FIG. 3 depicts a configuration example of hardware of a managementserver used in the second embodiment. In the management server 100, aprocessor 101 controls the entire apparatus. A memory 102 and aplurality of peripheral devices are coupled to the processor 101 througha bus 109. The processor 101 may be a multiprocessor. The processor 101is, for example, a CPU, a micro processing unit (MPU), or a digitalsignal processor (DSP). An electronic circuit, such as an applicationspecific integrated circuit (ASIC) and a programmable logic device(PLD), may realize at least part of the functions realized by programsexecuted by the processor 101.

The memory 102 is used as a main storage apparatus of the managementserver 100. At least part of programs of an operating system (OS) andapplication programs to be executed by the processor 101 is temporarilystored in the memory 102. Various types of data necessary for processesexecuted by the processor 101 are stored in the memory 102. An exampleof the memory 102 includes a volatile semiconductor storage apparatussuch as a random access memory (RAM).

Examples of the peripheral devices coupled to the bus 109 include astorage apparatus 103, a graphics processing apparatus 104, an inputinterface 105, an optical drive apparatus 106, a device couplinginterface 107, and a network interface 108.

The storage apparatus 103 electrically or magnetically writes data toand reads data from a built-in recording medium. The storage apparatus103 is used as an auxiliary storage apparatus of the computer. Theprograms of the OS, the application programs, and various types of dataare stored in the storage apparatus 103. Examples of the storageapparatus 103 that may be used include a hard disk drive (HDD) and asolid state drive (SSD).

A monitor 21 is coupled to the graphics processing apparatus 104. Thegraphics processing apparatus 104 displays an image on a screen of themonitor 21 according to a command from the processor 101. Examples ofthe monitor 21 include a display apparatus using cathode ray tube (CRT)and a liquid crystal display apparatus.

A keyboard 22 and a mouse 23 are coupled to the input interface 105. Theinput interface 105 transmits a signal sent from the keyboard 22 or themouse 23 to the processor 101. The mouse 23 is an example of a pointingdevice, and other pointing devices may also be used. Examples of theother pointing devices include a touch panel, a tablet, a touchpad, anda trackball.

The optical drive apparatus 106 uses laser light or the like to readdata recorded in an optical disk 24. The optical disk 24 is a portablerecording medium recording data that may be read by reflection of light.Examples of the optical disk 24 include a digital versatile disc (DVD),a DVD-RAM, a compact disc read only memory (CD-ROM), a CD-recordable(R)/rewritable (RW).

The device coupling interface 107 is a communication interface forcoupling a peripheral device to the management server 100. For example,a memory apparatus 25 or a memory reader/writer 26 may be coupled to thedevice coupling interface 107. The memory apparatus 25 is a recordingmedium with a function of communicating with the device couplinginterface 107. The memory reader/writer 26 is an apparatus that writesdata to a memory card 27 or reads data from the memory card 27. Thememory card 27 is a card-type recording medium.

The network interface 108 is coupled to the network 20. The networkinterface 108 transmits and receives data to and from another computeror a communication device through the network 20.

The hardware configuration may realize processing functions of thesecond embodiment. The apparatus illustrated in the first embodiment mayalso be realized by hardware similar to the management server 100illustrated in FIG. 3.

The management server 100 executes, for example, a program recorded in acomputer-readable recording medium to realize the processing functionsof the second embodiment. The program describing the details ofprocesses to be executed by the management server 100 may be recorded invarious recording media. For example, the program to be executed by themanagement server 100 may be stored in the storage apparatus 103. Theprocessor 101 loads at least part of the program in the storageapparatus 103 to the memory 102 to execute the program. Alternatively,the program to be executed by the management server 100 may be recordedin a portable recording medium, such as the optical disk 24, the memoryapparatus 25, and the memory card 27. The program stored in the portablerecording medium may be installed on the storage apparatus 103 andexecuted based on, for example, the control from the processor 101.Alternatively, the processor 101 may directly read the program from theportable recording medium to execute the program.

Next, failure influence range detecting functions included in themanagement server 100 will be described.

FIG. 4 is a block diagram illustrating failure influence range detectingfunctions of a management server. The management server 100 includes anoperation state information collecting unit 110, an operation stateinformation storage unit 120, an influence propagation model creatingunit 130, an influence propagation model storage unit 140, a failureinformation collecting unit 150, an influence range searching unit 160,and an influence range display unit 170.

The operation state information collecting unit 110 collects informationregarding the operation state of the devices in the system through themonitoring server 30. For example, the operation state informationcollecting unit 110 collects configuration information of the system,use resource information indicating the use status of resources of eachdevice, a message log, and the like. The operation state informationcollecting unit 110 collects the information at, for example, thebeginning of the system operation as well as at a large-scale change inthe system or at a periodical timing such as once a month.

The operation state information storage unit 120 stores the informationcollected by the operation state information collecting unit 110. Forexample, the operation state information storage unit 120 stores systemconfiguration information 121, use resource information 122, a messagelog 123, and the like.

The influence propagation model creating unit 130 creates an influencepropagation model of each piece of software based on the informationstored in the operation state information storage unit 120. Theinfluence propagation model creating unit 130 includes an informationtransmission path detecting unit 131, an influence propagation directiondetermining unit 132, and an influence propagation directionsupplementing unit 133.

The information transmission path detecting unit 131 performscorrelation analysis between apparatuses regarding the use status ofresources and detects a communication path between correlatedapparatuses as an information transmission path.

The influence propagation direction determining unit 132 analyzes theco-occurrence relationship between adjacent apparatuses regardingmessages and determines the propagation direction of influence. Forexample, when an apparatus outputs a message at a high probabilitywithin a given time after another apparatus outputs a message, theinfluence propagation direction determining unit 132 determines that theinfluence is propagated from the apparatus outputting the message firstto the apparatus outputting the message second.

The influence propagation direction supplementing unit 133 supplementsthe propagation path of the influence not detected by the influencepropagation direction determining unit 132. For example, the influencepropagation direction supplementing unit 133 traces the informationtransmission path extracted by the information transmission pathdetecting unit 131 toward the downstream in the influence propagationdirection determined by the influence propagation direction determiningunit 132 and supplements the influence propagation direction toward thedownstream devices up to the end of the information transmission path.

The influence propagation model storage unit 140 stores influencepropagation model information 141, 142, . . . corresponding to thepieces of software indicating the influence propagation models createdby the influence propagation model creating unit 130.

The failure information collecting unit 150 collects failure informationindicating a failure in any one of the devices from the monitoringserver 30.

When the failure information collecting unit 150 collects the failureinformation, the influence range searching unit 160 searches for theinfluence range of the failure based on the influence propagation modelinformation 141, 142, . . . .

The influence range display unit 170 displays the searched influencerange. The influence range display unit 170 may also notify a designatedadministrator or user of the occurrence of failure and the influencerange.

The lines coupling the elements illustrated in FIG. 4 indicate part ofthe communication paths, and communication paths other than theillustrated communication paths may also be set. The function of eachelement illustrated in FIG. 4 may be realized by, for example, causingthe computer to execute a program module corresponding to the element.The operation state information storage unit 120 and the influencepropagation model storage unit 140 are realized by using part of thestorage area of the memory 102 or the storage apparatus 103 of themanagement server 100.

Next, the information stored in the operation state information storageunit 120 will be described in detail.

FIG. 5 depicts an example of information stored in an operation stateinformation storage unit. The system configuration information 121indicating the coupling relationship between the devices to be managedis stored in the operation state information storage unit 120. Aplurality of pairs of two directly coupled devices are registered in thesystem configuration information 121.

Use resource information 122 a, 122 b, . . . corresponding to thedevices is stored in the operation state information storage unit 120.The use resource information 122 a, 122 b, . . . includes results ofperiodical measurement of the use status of resources, such as a CPU anda memory, of corresponding devices. In the case of the use statusrelated to the CPU, the CPU usage at every certain time is indicated inthe use resource information 122 a, 122 b, . . . in chronological order.In the case of the use status related to the memory, the used memorycapacity at every certain time is indicated in the use resourceinformation 122 a, 122 b, . . . .

Message logs 123 a, 123 b, . . . corresponding to the kinds of softwareare further stored in the operation state information storage unit 120.For example, messages output by a plurality of devices through executionof software named “software a” are included in the message log 123 a.Each message includes information, such as time of output, outputdevice, kind of message, and content of message.

Next, the information stored in the influence propagation model storageunit 140 will be described in detail.

FIG. 6 depicts an example of information stored in an influencepropagation model storage unit. The influence propagation modelinformation 141, 142, . . . corresponding to the pieces of software isstored in the influence propagation model storage unit 140. For example,the influence propagation model information 141 is informationindicating the influence propagation model regarding the software named“software a.” For example, records of each coupling relationship betweentwo devices are registered in the influence propagation modelinformation 141. Each record is provided with fields of identifier (ID),device at first end, device at second end, transmission, “to the right,”“to the left,” and weight.

An identifier of the coupling relationship (coupling relationship ID) isset in the field of ID. The name of the device at one end in thecoupling relationship is set in the field of device at first end. Thename of the device at second end that is the other end in the couplingrelationship is set in the field of device at second end. The number ofdevice pairs using the corresponding coupling relationship as theinformation transmission path is set in the field of transmission. Aflag indicating whether or not the influence propagates from the deviceat first end to the device at second end is set in the field of “to theright.” When the influence propagates from the device at first end tothe device at second end, “1” is set in the field of “to the right.”When the influence does not propagate from the device at first end tothe device at second end, “0” is set in the field. A flag indicatingwhether or not the influence propagates from the device at second end tothe device at first end is set in the field of “to the left.” When theinfluence propagates from the device at second end to the device atfirst end, “1” is set in the field of “to the left.” When the influencedoes not propagate from the device at second end to the device at firstend, “0” is set in the field. A value (weight) indicating the magnitudeof the influence of failure is set in the field of weight.

An influence propagation model 41 is defined by the influencepropagation model information 141. In the influence propagation model41, each device is expressed by a node, and the nodes in the couplingrelationship are coupled by a line, for example. In the influencepropagation model 41, the weight of the corresponding couplingrelationship is expressed by the thickness of the line, for example. Inthe influence propagation model 41, the propagation direction of theinfluence is expressed by an arrow at one end of the coupling line.

The system configured in this way creates the influence propagationmodel, and upon failure, the influence propagation model is used todisplay the range of the influence of the failure.

Next, a procedure of creating the influence propagation model based onthe collected operation state information will be described in detail.

FIG. 7 is a flow chart illustrating an example of a procedure of aninfluence propagation model creating process. The influence propagationmodel creating process is started in response to, for example, aninfluence propagation model creation instruction input by the user.Alternatively, the influence propagation model creating process may bestarted at a preset time. Furthermore, the influence propagation modelcreating process may be periodically executed at certain time intervals.The process illustrated FIG. 7 will be described along with stepnumbers.

[S101] The information transmission path detecting unit 131 in theinfluence propagation model creating unit 130 reads the systemconfiguration information 121 from the operation state informationstorage unit 120.

[S102] The information transmission path detecting unit 131 executes aninformation transmission path detecting process. Details of theinformation transmission path detecting process will be described later(see FIG. 10). As a result of the information transmission pathdetecting process, values are set in the fields of transmission in eachpiece of the influence propagation model information 141, 142, . . . .

[S103] The influence propagation direction determining unit 132 in theinfluence propagation model creating unit 130 executes an influencepropagation direction determining process. Details of the influencepropagation direction determining process will be described later (seeFIG. 14).

[S104] The influence propagation direction supplementing unit 133 in theinfluence propagation model creating unit 130 uses the determinationresult of the influence propagation direction determining process toestimate the influence propagation direction of an undetermined path tosupplement the influence propagation direction. Details of the influencepropagation direction supplementing process will be described later (seeFIGS. 18A and 18B).

[S105] The influence propagation direction supplementing unit 133executes a weighting process of the coupling relationship. Details ofthe weighting process will be described later (see FIG. 20).

The influence propagation model information 141, 142, . . .corresponding to the pieces of software as illustrated in FIG. 6 may becreated in the procedure. Each process of S102 to S105 illustrated inFIG. 7 will be described in detail.

The information transmission path detecting process will be describedwith reference to FIGS. 8 to 12.

FIG. 8 depicts a detection method of an information transmission path.In the second embodiment, correlation analysis of use resources betweendevices is used to detect the information transmission path. Thecorrelation analysis is quantification of a correlation between twovariables. A numerical value indicating the correlation is called acorrelation coefficient. The correlation coefficient is, for example, aPearson's correlation coefficient. The larger the value of thecorrelation coefficient, the higher the correlation between twovariables.

The information transmission path detecting unit 131 performs thecorrelation analysis of all combinations of two devices among thedevices to be managed. For example, when the information transmissionpath detecting unit 131 performs the correlation analysis of the deviceA and the device B, the information transmission path detecting unit 131calculates the correlation coefficient between the use resourceinformation 122 a of the device A and the use resource information 122 bof the device B. If the correlation coefficient is greater than a giventhreshold (for example, “0.7”), there is a correlation between thedevice A and the device B regarding the status of resource usage.Although the threshold for determining whether or not there is acorrelation is “0.7” in the example of FIG. 8, the value is an example,and another threshold, such as “0.5,” may also be used as a threshold.

Information regarding cooperative processing may be transmitted betweenthe devices with correlation in the use status of resources. Therefore,the information transmission path detecting unit 131 detects thecommunication path between the correlated devices as an informationtransmission path. The information transmission path is not simply apath that allows communication, but is a path in which informationinfluencing the partner apparatus is transmitted in the actualoperation. For example, even if there is a path between two apparatuseson the configuration diagram of the coupling relationship, the path maynot be the information transmission path. The path may be a path that isphysically coupled, but not actually used much. The path may be a pathcoupled in the design, but not currently coupled.

As illustrated in FIG. 8, when the paths between the devices withcorrelation in the use status of resources are detected as informationtransmission paths, part of the detected paths may overlap.

FIG. 9 depicts an example in which information transmission pathsoverlap. In the detected overlapping paths, it is more likely thatinformation influencing the devices with each other is transmitted.Therefore, the information transmission path detecting unit 131determines that the devices with more overlapping correlated paths arestrongly related and weights the paths. For each coupling path betweenadjacent devices, the number of information transmission paths passingthrough the path is set as a numerical value of the weight, and thenumerical value is used as a value of transmission of the coupling path.

In the example of FIG. 9, the devices are coupled in the order of adevice A, a device C, a device D, and a device B. The device A and thedevice B are correlated, and the device A and the device D are alsocorrelated. In this case, the number of information transmission pathspassing through the coupling path between the device A and the device Cis two. Therefore, “2” is set as a value of transmission for thecoupling path between the device A and the device C. Similarly, thenumber of information transmission paths passing through the couplingpath between the device C and the device D is two. Therefore, “2” is setas a value of transmission for the coupling path between the device Cand the device D. The number of overlapping information transmissionpaths in the section between the device D and the device B is one.Therefore, “1” is set as a value of transmission for the coupling pathbetween the device D and the device B.

In this way, the correlation analysis of the use status of resourcesbetween devices is performed to detect the information transmissionpaths, and the value corresponding to the number of informationtransmission paths passing through the coupling relationship betweenadjacent apparatuses is set as the value of transmission of the couplingrelationship.

The procedure of the information transmission path detecting processwill be described in detail.

FIG. 10 is a flow chart illustrating an example of a procedure of aninformation transmission path detecting process. The process illustratedin FIG. 10 will be described along with step numbers.

[S111] The information transmission path detecting unit 131 reads thesystem configuration information 121 from the operation stateinformation storage unit 120.

[S112] The information transmission path detecting unit 131 extracts apath of communication from an end device to another end device in thecoupling relationship based on the system configuration information 121.Details of the path extracting process will be described later (see FIG.11). As a result of the path extracting process, a path list indicatingthe extracted paths is created.

[S113] The information transmission path detecting unit 131 extracts thecoupling relationship between adjacent devices and sets the couplingrelationship in common influence propagation model information 140-1.For example, the information transmission path detecting unit 131creates the common influence propagation model information 140-1 in aninitial state. The information transmission path detecting unit 131 thenprovides an ID to each device pair in the coupling relationship based onthe system configuration information 121 and adds the recordcorresponding to each device pair to the common influence propagationmodel information 140-1. For the device at first end and the device atsecond end of the record to be added, the information transmission pathdetecting unit 131 sets the names of the devices included in the devicepair corresponding to the record. In this case, the informationtransmission path detecting unit 131 regards the device on the left asthe device at first end and regards the device on the right as thedevice at second end in the path indicated in the device list created inS112. At this point, the values in the fields of “to the right,” “to theleft,” and weight are “0” in each record registered in the commoninfluence propagation model information 140-1. The informationtransmission path detecting unit 131 stores the created common influencepropagation model information 140-1 in the memory 102.

[S114] The information transmission path detecting unit 131 creates anode list 42 listing the devices included in the system. The names ofthe devices are registered in the node list 42 without duplication.

[S115] The information transmission path detecting unit 131 selects oneunselected device from the node list 42.

[S116] The information transmission path detecting unit 131 uses useresource information 112 of the selected device and another device toperform the correlation analysis.

[S117] The information transmission path detecting unit 131 determineswhether there is another correlated device. If there is anothercorrelated device, the information transmission path detecting unit 131advances the process to S118. If there is no correlated device, theinformation transmission path detecting unit 131 advances the process toS119.

[S118] For each of the other correlated devices, the informationtransmission path detecting unit 131 executes a path deciding process ofsearching for the information transmission path between the selecteddevice and the other device. Details of the path deciding process willbe described later (see FIG. 12). As a result of the path decidingprocess, a value corresponding to the number of information transmissionpaths passing through the corresponding coupling relationship is set inthe field of transmission in each record of the common influencepropagation model information 140-1.

[S119] The information transmission path detecting unit 131 determineswhether or not there is an unselected node in the node list 42. If thereis an unselected node, the information transmission path detecting unit131 advances the process to S115. If there is no unselected node, theinformation transmission path detecting unit 131 ends the informationtransmission path detecting process.

Next, details of the path extracting process will be described.

FIG. 11 is a flow chart illustrating an example of a procedure of a pathextracting process. The process illustrated in FIG. 11 will be describedalong with step numbers.

[S131] The information transmission path detecting unit 131 reads thesystem configuration information 121.

[S132] The information transmission path detecting unit 131 figures outthe coupling relationship between the devices based on the systemconfiguration information 121 and creates a path list 43 indicating acommunication path from an end device to another end device. The enddevice is a device in which the number of directly coupled adjacentdevices is only one.

For example, when a plurality of devices are coupled in a couplingrelationship as illustrated in a path model 44, a device A, a device B,and a device 2 are end devices. In this case, path informationindicating the path from the device A to the device B, the path from thedevice A to the device 2, and the path from the device 2 to the device Bare registered in the path list 43. A path ID is provided to the pathinformation registered in the path list 43. The names of the devices onthe path from the device at one end of the path to the device at anotherend are set in the path information.

The information transmission path detecting unit 131 stores the createdpath list 43 in the memory 102 and ends the path extracting process.

Next, the path deciding process will be described in detail.

FIG. 12 is a flow chart illustrating an example of a procedure of a pathdeciding process. The process illustrated in FIG. 12 will be describedalong with step numbers.

[S141] The information transmission path detecting unit 131 reads thepath list 43 from the memory.

[S142] The information transmission path detecting unit 131 extracts,from the path list 43, the path information including both of twodevices determined to be correlated in the correlation analysis of S116.

[S143] The information transmission path detecting unit 131 extracts acombination of adjacent devices from the two correlated devices and thedevices between these devices based on the extracted path information.

[S144] The information transmission path detecting unit 131 reads thecommon influence propagation model information from the memory 102.

[S145] The influence propagation model storage unit 140 adds 1 to thevalue of transmission in the record corresponding to the extractedcombination of devices in the common influence propagation modelinformation 140-1.

For example, in the coupling relationship illustrated in the path model44, it is assumed that the device A and the device B are correlated, andthe device B and the device D are also correlated. In this case, thevalue of transmission in the record corresponding to the set of thedevice A and the device C is “1.” The value of transmission in therecord corresponding to the set of the device C and the device D is also“1.” The value of transmission in the record corresponding to the set ofthe device D and the device B is “2.” The coupling relationship betweenthe device 2 and the device A is not used as an information transmissionpath, and the value of transmission in the record corresponding to theset of the device 2 and the device A is “0.”

In this way, the information propagation path is detected, and theresults are set in the common influence propagation model information140-1.

Next, the influence propagation direction determining process will bedescribed with reference to FIGS. 13 to 15.

FIG. 13 depicts an example of determining an influence propagationdirection. FIG. 13 illustrates an example of determining theco-occurrence relationship regarding the software named “software a.”The co-occurrence relationship between messages is used to determine theinfluence propagation direction.

For example, the time that each device has output a message is found outbased on the message log 123 a of the software to be determined.Therefore, the influence propagation direction determining unit 132calculates the probability of output of a message by a device within agiven period after the output of a message by another device and setsthe probability as a co-occurrence probability.

For example, the influence propagation direction determining unit 132regards the device that outputs the message first as a first messageoutput device and regards the device that outputs the message second asa second message output device. The influence propagation directiondetermining unit 132 creates a co-occurrence probability table 50 inwhich the records of the pairs of devices are registered. Subsequently,the influence propagation direction determining unit 132 calculates theco-occurrence probability for each pair of devices and sets theco-occurrence probability in the co-occurrence probability table 50. Theinfluence propagation direction determining unit 132 then extracts apair of devices with the co-occurrence probability greater than athreshold (for example, “0.7”) as a pair of devices in the co-occurrencerelationship.

When a pair of devices in the co-occurrence relationship is detected, itmay be predicted that the influence of a failure or the like propagatesfrom the first message output device to the second message output devicein the pair of devices. Therefore, the influence propagation directiondetermining unit 132 determines that the direction from the firstmessage output device to the second message output device in theco-occurrence relationship is the influence propagation direction.

FIG. 14 is a flow chart illustrating an example of a procedure of aninfluence propagation direction determining process. The processillustrated in FIG. 14 will be described along with step numbers.

[S201] The influence propagation direction determining unit 132 readsthe message log of each piece of software from the operation stateinformation storage unit 120.

[S202] The influence propagation direction determining unit 132 performsco-occurrence analysis of messages for each combination of devices basedon the message log of each piece of software.

[S203] The influence propagation direction determining unit 132determines whether or not there is a co-occurrence relationship betweendevices in at least one combination. If there is a co-occurrencerelationship, the influence propagation direction determining unit 132advances the process to S204. If there is no co-occurrence relationship,the influence propagation direction determining unit 132 ends theinfluence propagation direction determining process.

[S204] The influence propagation direction determining unit 132 createsco-occurrence device lists 51, 52, . . . corresponding to the pieces ofsoftware. The pairs of devices in the co-occurrence relationship are setin the co-occurrence device lists 51, 52, . . . . In this case, theinfluence propagation direction determining unit 132 creates theinfluence propagation model information 141, 142, . . . corresponding tothe pieces of software based on the common influence propagation modelinformation 140-1. For example, the influence propagation directiondetermining unit 132 sets a plurality of copies of the common influencepropagation model information 140-1 as the influence propagation modelinformation 142, 142, . . . corresponding to the pieces of software.

[S205] The influence propagation direction determining unit 132 selectsone unselected co-occurrence device list.

[S206] The influence propagation direction determining unit 132 selectsone pair of devices in the co-occurrence relationship (co-occurrencepair) from the selected co-occurrence device list.

[S207] The influence propagation direction determining unit 132 executesa direction providing process regarding the selected co-occurrence pairwith respect to the influence propagation model information of the samesoftware as in the selected co-occurrence device list. Details of thedirection providing process will be described later (see FIG. 15).

[S208] The influence propagation direction determining unit 132determines whether or not there is an unselected co-occurrence pairamong the co-occurrence pairs registered in the selected co-occurrencelist. If there is an unselected co-occurrence pair, the influencepropagation direction determining unit 132 advances the process to S206.If there is no unselected co-occurrence pair, the influence propagationdirection determining unit 132 advances the process to S209.

[S209] The influence propagation direction determining unit 132determines whether or not there is an unselected co-occurrence devicelist. If there is an unselected co-occurrence device list, the influencepropagation direction determining unit 132 advances the process to S205.If there is no unselected co-occurrence device list, the influencepropagation direction determining unit 132 ends the influencepropagation direction determining process.

Next, the direction providing process will be described in detail.

FIG. 15 is a flow chart illustrating an example of a procedure of adirection providing process. The process illustrated in FIG. 15 will bedescribed along with step numbers.

[S211] The influence propagation direction determining unit 132 readsthe path list 43 from the memory 102.

[S212] The influence propagation direction determining unit 132 extractsa path including the co-occurrence pair selected in S206 from the pathlist 43.

[S213] The influence propagation direction determining unit 132determines whether or not the order of the co-occurrence pair is thesame as the order of registration in the path list 43. As for the orderof the co-occurrence pair, the device set on the left in theco-occurrence list is the influencing device (first in order), and thedevice set on the right is the influenced device (second in order). Inthe path list 43, the device on the left side is the first in order, andthe device on the right side is the second in order. If the orders arethe same, the influence propagation direction determining unit 132advances the process to S214. If the orders are opposite, the influencepropagation direction determining unit 132 advances the process to S215.

[S214] The influence propagation direction determining unit 132 sets avalue “1,” which indicates there is propagation of influence, in thefield of “to the right” in the record including the pair of devicescorresponding to the selected co-occurrence pair in the influencepropagation model regarding the same software as in the selectedco-occurrence list. Subsequently, the direction providing process ends.

[S215] The influence propagation direction determining unit 132 sets avalue “1,” which indicates there is propagation of influence, in thefield of “to the left” in the record including the pair of devicescorresponding to the selected co-occurrence pair in the influencepropagation model regarding the same software as in the selectedco-occurrence list. Subsequently, the direction providing process ends.

In this way, the influence propagation direction upon failure is set inthe influence propagation model information 141, 142, . . . . However,the determination of the influence propagation direction is based on thelogs of messages output at the execution of the software, and theinfluence propagation direction may not be determined for a device inwhich the log of message of the software is not recorded. Therefore, theinfluence propagation direction supplementing unit 133 executes asupplementing process of the influence propagation direction. Theinfluence propagation direction supplementing process will be describedwith reference to FIGS. 16 to 19.

FIG. 16 depicts an example of supplementing an influence propagationdirection. FIG. 16 illustrates an information transmission path from adevice A to a device B. The influence propagation direction is extractedbased on the co-occurrence relationship between output messages or thelike at part of the information transmission path. In the example ofFIG. 16, the influence of failure is propagated in the direction from adevice C to a device D.

The information is propagated to the downstream, and in the downstreamof the extracted influence propagation direction, it may be estimatedthat the influence of failure is further propagated to the downstream.It may also be estimated that the propagation of the influence offailure ends at the end device of the information transmission path. Itmay be estimated that the influence of failure is not propagated on theupstream of the extracted influence propagation direction.

Therefore, the influence propagation direction supplementing unit 133supplements the influence propagation direction toward the device on thedownstream in the influence propagation direction in the path of theinformation transmission path in which the influence propagationdirections extracted in the logs overlap. In the example of FIG. 16, theinfluence propagation direction from the device D to the device B issupplemented.

FIG. 17 depicts examples of supplement patterns of an influencepropagation direction. In FIG. 17, the devices on the informationtransmission path are arranged in the order registered in the path list43. As for the pairs of adjacent devices on the information transmissionpath, the device on the left in the arrangement of the path list 43 isregarded as the device at first end, and the device on the right isregarded as the device at second end when the pairs are registered inthe influence propagation model information 141, 142, . . . .

When the influence propagation direction is to the right (direction fromthe device at first end to the device at second end) as in the case ofthe software named “software a,” the influence propagation direction issupplemented to the right of the device at second end. When theinfluence propagation direction is to the left (direction from thedevice at second end to the device at first end) as in a case ofsoftware named “software b,” the influence propagation direction issupplemented to the left of the device at first end.

The co-occurrence relationship may be detected in the same device as ina case of software named “software c” and software named “software d.”In this case, the influence propagation direction is supplemented foreach piece of software.

The influence of failure is propagated through, for example,communication at the execution of software. Therefore, the supplement ofthe influence propagation direction of software may be stopped at thedevice including the software. However, different pieces of software maybe operating together. In that case, the influence propagates betweenthe pieces of software operating together. Therefore, the influencepropagation direction may be supplemented across a plurality of piecesof software operating together.

For example, there may be a case where software named “software e” andthe software named “software d” operate together. It is assumed that thesoftware named “software e” is implemented in a device D, a device E,and a device F, but is not implemented in a device C and a device A. Onthe other hand, it is assumed that the software named “software f” isimplemented in the device A, the device C, and the device D. In thiscase, the influence propagation direction is supplemented up to thedevice D when it is determined that there is a co-occurrencerelationship between the device F and the device E regarding thesoftware named “software e” and that there is propagation of influenceto the left. When only the software named “software e” is considered,the influence propagation direction is not supplemented for the device Cand the device A not including the software. However, when there is aco-occurrence relationship between the device D and the device Cregarding the software named “software f,” the influence propagationdirection is set based on the co-occurrence relationship, and theinfluence propagation direction is supplemented in a range in which thesoftware named “software f” is implemented. The failure influence rangeof a plurality of pieces of software operating together may be displayedon top of each other upon failure to properly display the influencerange of the failure.

Next, the influence propagation direction supplementing process will bedescribed in detail.

FIGS. 18A and 18B are flow charts illustrating an example of a procedureof an influence propagation direction supplementing process. The processillustrated in FIGS. 18A and 18B will be described along with stepnumbers.

[S301] The influence propagation direction supplementing unit 133 readsone piece of unprocessed influence propagation model information.

[S302] The influence propagation direction supplementing unit 133selects one record indicating the coupling relationship between twodevices included in the influence propagation model information.

[S303] The influence propagation direction supplementing unit 133 checkswhether the influence propagation direction is to the right or to theleft. For example, the influence propagation direction supplementingunit 133 acquires the value in the field of “to the right” and the valuein the field of “to the left” in the selected record.

[S304] The influence propagation direction supplementing unit 133determines whether or not one of the value in the field of “to theright” and the value in the field of “to the left” is greater than 0. Ifat least one of the values is greater than 0, the influence propagationdirection supplementing unit 133 advances the process to S305. If bothof the values are 0, the influence propagation direction supplementingunit 133 advances the process to S307.

[S305] The influence propagation direction supplementing unit 133 storesinformation indicating the direction of the propagation of influence(right or left) in the memory. If the value greater than 0 is set in thefield of “to the right,” information indicating the right is stored. Ifthe value greater than 0 is set in the field of “to the left,”information indicating the left is stored.

[S306] The influence propagation direction supplementing unit 133executes a direction supplementing process. Details of the directionsupplementing process will be described later (see FIG. 19). As a resultof the direction supplementing process, the direction of the propagationof influence corresponding to the propagation of influence not detectedin the co-occurrence relationship is added to the influence propagationmodel information 141, 142, . . . .

[S307] The influence propagation direction supplementing unit 133determines whether or not all of the coupling relationships in the readinfluence propagation model information are selected. If there is anunselected coupling relationship, the influence propagation directionsupplementing unit 133 advances the process to S302. If all of thecoupling relationships are already selected, the influence propagationdirection supplementing unit 133 advances the process to S308.

[S308] The influence propagation direction supplementing unit 133determines whether or not processing of all of the influence propagationmodel information 141, 142, . . . is completed. If processing of all ofthe influence propagation model information 141, 142, . . . iscompleted, the influence propagation direction supplementing unit 133ends the influence propagation direction supplementing process. If thereis unprocessed influence propagation model information, the influencepropagation direction supplementing unit 133 advances the process toS301.

Next, the direction supplementing process will be described in detail.

FIG. 19 is a flow chart illustrating an example of a procedure of adirection supplementing process. The process illustrated in FIG. 19 willbe described along with step numbers.

[S311] The influence propagation direction supplementing unit 133 readsthe path list 43.

[S312] The influence propagation direction supplementing unit 133extracts, from the path list 43, the path including both of the devicesin the coupling relationship selected in S302.

[S313] The influence propagation direction supplementing unit 133specifies the influence propagation direction of the co-occurrencerelationship. The influence propagation direction is the directionindicated in the information stored in the S305.

[S314] The influence propagation direction supplementing unit 133determines whether or not the direction of the propagation of influenceis to the right. If the direction is to the right, the influencepropagation direction supplementing unit 133 advances the process toS315. If the direction is to the left, the influence propagationdirection supplementing unit 133 advances the process to S318.

[S315] The influence propagation direction supplementing unit 133determines whether or not there is a device on the right side in thepath extracted in S312. If there is a device on the right side, theinfluence propagation direction supplementing unit 133 advances theprocess to S316. If there is no device on the right side, the influencepropagation direction supplementing unit 133 ends the directionsupplementing process.

[S316] The influence propagation direction supplementing unit 133extracts all of the coupling relationships between the devices on theright side of the devices in the co-occurrence relationship from thepath extracted in S312.

[S317] The influence propagation direction supplementing unit 133 adds 1to the value in the field of “to the right” in the record correspondingto the extracted coupling relationship in the influence propagationmodel information read in S301. Subsequently, the directionsupplementing process ends.

[S318] The influence propagation direction supplementing unit 133determines whether or not there is a device on the left side in the pathextracted in S312. If there is a device on the left side, the influencepropagation direction supplementing unit 133 advances the process toS319. If there is no device on the left side, the influence propagationdirection supplementing unit 133 ends the direction supplementingprocess.

[S319] The influence propagation direction supplementing unit 133extracts all of the coupling relationships between the devices on theleft side of the devices in the co-occurrence relationship from the pathextracted in S312.

[S320] The influence propagation direction supplementing unit 133 adds 1to the value in the field of “to the left” in the record correspondingto the extracted coupling relationship in the influence propagationmodel information read in S301. Subsequently, the directionsupplementing process ends.

In this way, the process of supplementing the influence propagationdirection is executed. After the completion of the influence propagationdirection supplementing process, the coupling relationship betweenadjacent devices is weighted.

FIGS. 20A and 20B are flow charts illustrating an example of a procedureof a weighting process. The process illustrated in FIGS. 20A and 20Bwill be described along with step numbers.

[S321] The influence propagation direction supplementing unit 133 readsone piece of influence propagation model information.

[S322] The influence propagation direction supplementing unit 133selects the record of one coupling relationship from the read influencepropagation model information.

[S323] The influence propagation direction supplementing unit 133 addsthe values in the fields of transmission, “to the right,” and “to theleft” in the selected record.

[S324] The influence propagation direction supplementing unit 133 storesthe total value in the field of weight in the selected record.

[S325] The influence propagation direction supplementing unit 133determines whether or not all of the coupling relationships indicated inthe read influence propagation mode information are selected. If all ofthe coupling relationships are already selected, the influencepropagation direction supplementing unit 133 advances the process toS326. If there is an unselected coupling relationship, the influencepropagation direction supplementing unit 133 advances the process toS322.

[S326] The influence propagation direction supplementing unit 133determines whether or not processing of all of the influence propagationmodel information is completed. If processing of all of the influencepropagation model information is completed, the influence propagationdirection supplementing unit 133 ends the weighting process. If there isunprocessed influence propagation model information, the influencepropagation direction supplementing unit 133 advances the process toS321.

In this way, the influence propagation model information is generated.When a failure occurs in any one of the devices, the influence range ofthe failure is searched based on the generated influence propagationmodel information, and the influence range is displayed.

A failure handling supporting process upon failure will be describedwith reference to FIGS. 21 to 27. Upon failure, the influence range ofthe failure is searched to support the failure analysis.

FIG. 21 depicts an example of searching an influence range upon failure.The influence propagation model information 141, 142, . . .corresponding to the pieces of software is stored in the influencepropagation model storage unit 140. For example, the influencepropagation model information 141 represents an influence propagationmodel 61 of the software named “software a.” The influence propagationmodel information 142 represents an influence propagation model 62 ofthe software named “software b.”

For example, when a failure regarding “software a” occurs in the deviceC, the failure information collecting unit 150 acquires informationregarding the failure, and the influence range searching unit 160searches the influence range of the failure. The influence range displayunit 170 then displays the influence propagation model 61 indicating theinfluence range of the failure. By displaying the influence propagationmodel 61, the administrator may take measures for the devices indescending order of influence and efficiently take measures against thefailure.

There may be other software operating together with the software inwhich the failure is detected. In that case, the influence propagationmodel displays the influence ranges corresponding to the pieces ofsoftware.

FIG. 22 depicts an example of an influence propagation model when aplurality of pieces of software operate together. For example, it isassumed that software named “software g” and software named “software h”operate together. When a plurality of pieces of software operatetogether, the propagation directions of influence in influencepropagation models 63 and 64 corresponding to the pieces of software areintegrated to generate an influence propagation model 65. Upon failure,the influence propagation model 65 is used to display the influencerange of the failure.

When the influence propagation model 65 reflecting the propagation ofinfluence of a plurality of pieces of software is not generated uponfailure, the influence propagation direction supplementing unit 133 usesthe plurality of directions corresponding to the pieces of software tosupplement the influence propagation direction again to generate theinfluence propagation model 65 of the plurality of pieces of software.

Next, the procedure of the failure handling supporting process will bedescribed in detail.

FIG. 23 is a flow chart illustrating an example of a procedure of afailure handling supporting process. The failure handling supportingprocess is executed, for example, when occurrence of failure isautomatically detected or when the user inputs failure occurrenceinformation. The process illustrated in FIG. 23 will be described alongwith step numbers.

[S401] The influence range searching unit 160 reads failure information71 stored in a failure information supplement folder designated inadvance. The failure information 71 is, for example, acquired by thefailure information collecting unit 150 from the monitoring server 30and stored in the failure information supplement folder. In the failureinformation 71, the name of the software with the failure and the nameof the device with the failure are set for each identifier (ID) of thefailure, for example.

[S402] After acquiring the failure information 71, the influence rangesearching unit 160 searches for the influence range of the failureindicated in the failure information 71. Details of the influence rangesearching process will be described later (see FIGS. 24A and 24B). As aresult of the influence range searching process, an influence range list72 is generated. The devices influenced by the failure (influenceddevices) and the weights of the influence of the devices are set in theinfluence range list 72.

[S403] The influence range display unit 170 displays the influence rangeof the failure on the monitor 21 based on the influence range list 72.For example, the influence range display unit 170 displays an influencepropagation model representing a drawing of the content indicated in theinfluence range list 72. The thickness of the coupling line betweennodes in the influence propagation model displayed by the influencerange display unit 170 corresponds to the weight of the device on thedownstream of the propagation of influence passing through the couplingline, for example.

[S404] The influence range display unit 170 notifies the user, such asthe administrator, of the device influenced by the failure and theweight. For example, the influence range display unit 170 notifies theuser of the identifier of the device with the weight equal to or greaterthan a given value as a device likely to be influenced by the failure.

Next, the influence range searching process will be described.

FIG. 24 is a flow chart illustrating an example of a procedure of aninfluence range searching process. The process illustrated in FIG. 24will be described along with step numbers.

[S411] The influence range searching unit 160 selects one piece ofsoftware with a failure from the failure information 71.

[S412] The influence range searching unit 160 selects one device with afailure regarding the selected software from the failure information 71.

[S413] The influence range searching unit 160 determines whether or nota plurality of pieces of software operate together. For example, theinfluence range searching unit 160 determines that a plurality of piecesof software operate together when there is another piece of softwaredesignated in advance as software operating together with the selectedsoftware. If a plurality of pieces of software operate together, theinfluence range searching unit 160 advances the process to S414. If aplurality of pieces of software do not operate together, the influencerange searching unit 160 advances the process to S415.

[S414] The influence range searching unit 160 supplements the influencepropagation model information of the selected software based on theinfluence propagated by the other software operating together with theselected software. For example, the influence range searching unit 160adds the values, which are set in the corresponding record in theinfluence propagation model information of the other software with afailure operating together, to the fields of transmission, “to theright,” “to the left,” and weight in each record of the influencepropagation model information of the selected software.

[S415] The influence range searching unit 160 reads the influencepropagation model information of the selected software.

[S416] The influence range searching unit 160 traces the couplingrelationship from the device with the failure and searches for thedevice influenced by the failure. Details of the searching process willbe described later (see FIGS. 25A and 25B).

[S417] The influence range searching unit 160 determines whether or notall of the devices in which the selected software is failed areselected. If all of the devices are already selected, the influencerange searching unit 160 advances the process to S418. If there is anunprocessed device, the influence range searching unit 160 advances theprocess to S412.

[S418] The influence range searching unit 160 determines whether or notall of the pieces of software with failures are selected. If all of thepieces of software are already selected, the influence range searchingunit 160 advances the process to S419. If there is an unselected pieceof software, the influence range searching unit 160 advances the processto S411.

[S419] The influence range searching unit 160 outputs, as an influencerange search result, the influence range list 72 indicating theinfluence range searched in the searching process (S416).

Next, the searching process will be described in detail.

FIG. 25 is a flow chart illustrating an example of a procedure of asearching process. The process illustrated in FIG. 25 will be describedalong with step numbers.

[S431] The influence range searching unit 160 sets the device selectedin S412 as an influenced device.

[S432] The influence range searching unit 160 selects one couplingrelationship between adjacent devices (set of device at first end anddevice at second end) including the influenced device from the influencepropagation model information of the software selected in S411.

[S433] The influence range searching unit 160 determines whether or notthe selected device is the device at first end in the couplingrelationship. If the selected device is the device at first end, theinfluence range searching unit 160 advances the process to S434. If theselected device is the device at second end, the influence rangesearching unit 160 advances the process to S436.

[S434] The influence range searching unit 160 determines whether or notthe value in the field of “to the right” in the record of the selectedcoupling relationship is greater than 0. If the value in the field of“to the right” is greater than 0, the influence range searching unit 160advances the process to S435. If the value in the field of “to theright” is 0, the influence range searching unit 160 advances the processto S439.

[S435] The influence range searching unit 160 adds the device at secondend in the selected coupling relationship to the influenced devices. Theinfluence range searching unit 160 then advances the process to S438.

[S436] The influence range searching unit 160 determines whether or notthe value in the field of “to the left” in the record of the selectedcoupling relationship is greater than 0. If the value in the field of“to the left” is greater than 0, the influence range searching unit 160advances the process to S437. If the value in the field of “to the left”is 0, the influence range searching unit 160 advances the process toS439.

[S437] The influence range searching unit 160 adds the device at firstend in the selected coupling relationship to the influenced devices.

[S438] The influence range searching unit 160 outputs the influenceddevices and the weights of the records including the couplingrelationship as a source of extracting the influenced devices to theinfluence range list 72.

[S439] The influence range searching unit 160 determines whether or notthere is an unselected coupling relationship including an influenceddevice in the influence propagation model information of the selectedsoftware. If there is an unselected coupling relationship, the influencerange searching unit 160 advances the process to S432. If there is nounselected coupling relationship, the influence range searching unit 160ends the searching process.

In this way, the influence range of the failure is displayed in thefailure handling supporting process upon failure.

FIG. 26 depicts an example of displaying an influence range of failure.FIG. 26 illustrates a network configuration display screen 81 without afailure and a network configuration display screen 82 after a failure.In the example of FIG. 26, a failure occurs in the device A. The networkconfiguration display screen 82 illustrates the propagation of influenceof the failure to the device C, the device D, and the device B. Theweight of the influence regarding the influenced device is expressed bythe thickness of the arrow coupled to the device.

As a result of the display, the administrator may accurately figure outthe devices influenced by the failure. Moreover, the weight of theinfluence is expressed by the thickness of the line coupling thedevices, and the administrator may preferentially take measures for asignificantly influenced device. As a result, measures may beefficiently taken against the failure, and the negative influence of thefailure on the system operation may be reduced.

When the influence is propagated due to cooperative operation of aplurality of pieces of software, the influence propagation range isdisplayed by integrating the influence.

FIG. 27 depicts an example of displaying an influence propagation rangewhen a plurality of pieces of software operate together. In the exampleof FIG. 27, the devices influenced by the software named “software e”and the devices influenced by the software named “software f” arehighlighted in a network configuration display screen 83. As a result,the user may easily recognize that the influence is propagated due tothe cooperative operation of a plurality of pieces of software and thatthe devices up to the device B are influenced by the failure in thedevice 5.

Although the embodiments have been illustrated, the configuration ofeach element illustrated in the embodiments may be replaced with anotherconfiguration with a similar function. Alternatively, other arbitrarycomponents or processes may be added. Furthermore, two or more arbitraryconfigurations (features) in the embodiments may be combined.

All examples and conditional language provided herein are intended forthe pedagogical purposes of aiding the reader in understanding theinvention and the concepts contributed by the inventor to further theart, and are not to be construed as limitations to such specificallyrecited examples and conditions, nor does the organization of suchexamples in the specification relate to a showing of the superiority andinferiority of the invention. Although one or more embodiments of thepresent invention have been described in detail, it should be understoodthat the various changes, substitutions, and alterations could be madehereto without departing from the spirit and scope of the invention.

What is claimed is:
 1. A non-transitory computer-readable storage mediumstoring a program that causes a computer to execute a process, theprocess comprising: determining a communication path between two deviceswith a correlation in use status of resources as an informationtransmission path based on system configuration information indicating acoupling relationship between a plurality of devices included in anetwork and based on use resource information indicating temporalvariation in the use status of the resources of each of the plurality ofdevices; generating, for each of a plurality of software, an influencepropagation model in which a direction from a first device on theinformation transmission path to a second device adjacent to the firstdevice is set as an influence propagation direction of a failure of thesoftware in the information transmission path, when a co-occurrenceprobability indicating a probability that the second device outputs amessage through execution of the software within a certain time afterthe first device outputs a message through execution of the software isequal to or greater than a threshold, based on a message log generatedby accumulating a plurality of messages output by the plurality ofdevices after executing each of the plurality of software; acquiringfailure information indicating a failed device in which a failure occursin one of software among the plurality of software; specifying, as aninfluenced device influenced by the failure in the failed device, adevice reached by tracing the information transmission path from thefailed device in the influence propagation direction indicated in theinfluence propagation model of the one of software; and outputtinginformation indicating the influenced device.
 2. The storage mediumaccording to claim 1, wherein the generating the influence propagationmodel includes: setting a propagation direction from the first device toa direction of the second device, for a first adjacent couplingrelationship that is a coupling relationship between the first deviceand the second device on the influence propagation model; and tracingthe information transmission path in a direction opposite the firstdevice from the second device and setting a propagation direction in thetraced direction for a second adjacent coupling relationship that is acoupling relationship on the influence propagation model between deviceson the traced path.
 3. The storage medium according to claim 1, whereinthe generating the influence propagation model includes: setting, foreach of a plurality of adjacent coupling relationships indicatingcoupling relationships between adjacent devices on the influencepropagation model, a weight according to the number of informationtransmission paths passing through the adjacent coupling relationship,and the outputting includes outputting information indicating the weightof the adjacent coupling relationship.
 4. The storage medium accordingto claim 1, wherein the specifying the influenced device includesspecifying the influenced device from the influence propagation model ofeach of two or more software when the failure information regarding afailure related to the two or more software is acquired.
 5. An influencerange specifying method executed by a processor included in an influencerange specifying apparatus, the influence range specifying methodcomprising: determining a communication path between two devices with acorrelation in use status of resources as an information transmissionpath based on system configuration information indicating a couplingrelationship between a plurality of devices included in a network andbased on use resource information indicating temporal variation in theuse status of the resources of each of the plurality of devices;generating, for each of a plurality of software, an influencepropagation model in which a direction from a first device on theinformation transmission path to a second device adjacent to the firstdevice is set as an influence propagation direction of a failure of thesoftware in the information transmission path, when a co-occurrenceprobability indicating a probability that the second device outputs amessage through execution of the software within a certain time afterthe first device outputs a message through execution of the software isequal to or greater than a threshold, based on a message log generatedby accumulating a plurality of messages output by the plurality ofdevices after executing each of the plurality of software; acquiringfailure information indicating a failed device in which a failure occursin one of software among the plurality of software; specifying, as aninfluenced device influenced by the failure in the failed device, adevice reached by tracing the information transmission path from thefailed device in the influence propagation direction indicated in theinfluence propagation model of the one of software; and outputtinginformation indicating the influenced device.
 6. An influence rangespecifying apparatus, comprising: a memory; and a processor coupled tothe memory and configured to: store system configuration informationindicating a coupling relationship between a plurality of devicesincluded in a network, use resource information indicating temporalvariation in use status of resources of each of the plurality ofdevices, and a message log generated by accumulating a plurality ofmessages output by the plurality of devices after executing each of theplurality of software, determine a communication path between twodevices with a correlation in the use status of the resources as aninformation transmission path based on the system configurationinformation and the use resource information of each of the plurality ofdevices and generate, for each of the plurality of software, aninfluence propagation model in which a direction from a first device onthe information transmission path to a second device adjacent to thefirst device is set as an influence propagation direction of a failureof the software in the information transmission path, when aco-occurrence probability indicating a probability that the seconddevice outputs a message through execution of the software within acertain time after the first device outputs a message through executionof the software is equal to or greater than a threshold, based on themessage log, acquire failure information indicating a failed device inwhich a failure occurs in one of software among the plurality ofsoftware, specify, as an influenced device influenced by the failure inthe failed device, a device reached by tracing the informationtransmission path from the failed device in the influence propagationdirection indicated in the influence propagation model of the one ofsoftware, and output information indicating the influenced device. 7.The influence range specifying apparatus according to claim 6, whereinthe processor is configured to: set a propagation direction from thefirst device to a direction of the second device, for a first adjacentcoupling relationship that is a coupling relationship between the firstdevice and the second device on the influence propagation model, andtrace the information transmission path in a direction opposite thefirst device from the second device and setting a propagation directionin the traced direction for a second adjacent coupling relationship thatis a coupling relationship on the influence propagation model betweendevices on the traced path.
 8. The influence range specifying apparatusaccording to claim 6, wherein the processor is configured to: set, foreach of a plurality of adjacent coupling relationships indicatingcoupling relationships between adjacent devices on the influencepropagation model, a weight according to the number of informationtransmission paths passing through the adjacent coupling relationship,and output information indicating the weight of the adjacent couplingrelationship.
 9. The influence range specifying apparatus according toclaim 6, wherein the processor is configured to specify the influenceddevice from the influence propagation model of each of two or moresoftware when the failure information regarding a failure related to thetwo or more software is acquired.